Ep 154: 4-Step Approach to Bradycardia and Bradydysrhythmias

Not all bradycardias were created equal. How do we figure out when bradycardia is due to a medical illness and when it is a primary cardiac problem? What are the 4 immediate life threatening diagnosis that we have to entertain and address in the first few minutes of the sick bradycardic patients? What are some key ECG patterns that are sometimes missed by ED docs that can have devastating consequences? How can we better understand Torsades de Pointes by understanding AV blocks? How can we better understand Mobitz l and ll using 'The Dorian' approach? What is BRASH syndrome and how can we recognize it? In this main episode podcast 4-step Approach to Bradycardia and Bradydysrhythmias with electrophysiologist, educator and researcher Dr. Paul Dorian and Chair of Education for the ED at Cook County Hospital Dr. Tarlan Hedayati, we dig deep into bradycardia... Podcast production and editing by Anton Helman Voice editing by Sheza Qayyum, sound design my Yuang Chen & Anton Helman Written Summary and blog post by Winny Li, edited by Anton Helman April, 2021 Cite this podcast as: Helman, A. Hedayati, T. Dorian, P. Episode 154 - 4-Step Approach to Bradycardia and Bradydysrhythmias. Emergency Medicine Cases. Month, 2018. https://emergencymedicinecases.com/approach-bradycardia-bradydysrhythmias. Accessed [date] Go to part 2 of this 2-part podcast on bradycardia and bradydysrhythmias 4-step approach to bradycardia in the ED These steps are often done in parallel. * Stable vs. unstable * Symptomatic vs. asymptomatic * Determine the anatomic location causing the bradycardia: SA node, AV node or His-Purkinje * Assess for secondary causes of bradycardia Step 1: Determine if bradycardia is stable or unstable requiring immediate treatment The history and physical exam are paramount in helping make the decision of whether a patient with bradycardia is stable or unstable. Athletes and healthy people who are sleeping may normally have heart rates in the 30's, so the heart rate alone is almost never a sign of instability, unless there is another factor at play: underlying vasodilation, negative inotropic effect or intrinsic cardiac disease. Nonetheless, be extra-weary in patients with progressive bradycardia or worsening bradycardia: 50s then 40s then 30s then 20s. This is a sign of pre-arrest. Pearl: progressive bradycardia or worsening bradycardia over seconds-minutes is a peri-arrest sign. Cardiac output is dependent on heart rate and stroke volume. Depressed cardiac output in the setting of overt bradycardic shock will manifest as hypotension, as well as signs of decreased organ perfusion such as altered mental status, chest pain, dyspnea or syncope - all signs of an "unstable" bradycardic patient. However, be cautious to not miss occult bradycardic shock where the vasoconstrictor response in the setting of bradycardia maintains ones blood pressure and mental status. The patient however may still have low cardiac output and thus be "unstable". The clinical exam assessing for poor end-organ perfusion (altered LOA, cool extremities, low urine output etc) is critical in diagnosing occult bradycardic shock. Step 2: Symptomatic vs. asymptomatic It is important to determine if the bradycardia is causing symptoms (an older patient with underlying cardiac disease with chest pain and syncope), or if symptoms are the cause for bradycardia (vasovagal bradycardia), as this will direct management. Symptomatic bradycardia exists when the following 3 criteria are met: * The HR is slow * The patient has symptoms and * The symptoms are due to the slow HR